Traffic congestion is a common problem in many cities, and is often referred to by two terms: GRIDLOCK and SNARL. GRIDLOCK is an 8-letter term used to describe a situation where traffic is completely blocked due to a large number of vehicles in a small area. SNARL, a 5-letter term, is used to describe a situation where traffic is slowed down due to a large number of vehicles in a small area. Both terms are used to describe the same phenomenon, but GRIDLOCK is more severe than SNARL.